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This study was supported by Grant Number 07HQAG0124 between the National Academy of Sciences and the U.S. Geological Survey. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the organizations or agencies that provided support for the project.
Cover: Design by Anne Rogers. Map shows total nitrogen yields in kilograms per square kilometer per year determined by the SPAtially Referenced Regressions On Watershed Attributes (SPARROW) model.
International Standard Book Number-13: 978-0-309-26185-2
International Standard Book Number-10: 0-309-26185-6
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